Nonwoven fabrics, typified by spunbond nonwoven fabrics, are usually partially thermocompressed (emboss-treated) via an embossing roll in order to prevent the falling-off of fibers which form the nonwoven fabrics.
Emboss patterns (emboss shapes) formed by the thermocompression are usually formed regularly with a predetermined interval in the machine direction (Machine Direction: hereinafter, also referred to as MD) of the nonwoven fabric and in the direction crossing the machine direction (Cross Machine Direction: hereinafter, also referred to as CD).
The emboss patterns considerably affect the properties of the resultant nonwoven fabric such as strength, elongation, softness, resistance to falling-off of fibers and fuzz, and thus various emboss patterns have been proposed.
For example, Patent Literature 1 (JP-A-S57-167442) proposes a nonwoven fabric having an emboss pattern with unit patterns each being in the shape of rhombus or hexagon, wherein the emboss line of the unit pattern is formed by arranging a plurality of shapes such as square point, circular point, line and dotted line, with a predetermined interval.
Patent Literature 2 (JP-A-H11-335960) proposes a nonwoven fabric having an emboss pattern with unit patterns each being in the shape of lattice, wave, line, ellipse or arc, wherein the emboss line of the unit pattern is a straight line.